1 /* 2 * OMAP thermal driver interface 3 * 4 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ 5 * Contact: 6 * Eduardo Valentin <eduardo.valentin@ti.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 * 22 */ 23 24 #include <linux/device.h> 25 #include <linux/err.h> 26 #include <linux/mutex.h> 27 #include <linux/gfp.h> 28 #include <linux/kernel.h> 29 #include <linux/workqueue.h> 30 #include <linux/thermal.h> 31 #include <linux/cpufreq.h> 32 #include <linux/cpumask.h> 33 #include <linux/cpu_cooling.h> 34 35 #include "ti-thermal.h" 36 #include "ti-bandgap.h" 37 38 /* common data structures */ 39 struct ti_thermal_data { 40 struct thermal_zone_device *ti_thermal; 41 struct thermal_zone_device *pcb_tz; 42 struct thermal_cooling_device *cool_dev; 43 struct ti_bandgap *bgp; 44 enum thermal_device_mode mode; 45 struct work_struct thermal_wq; 46 int sensor_id; 47 }; 48 49 static void ti_thermal_work(struct work_struct *work) 50 { 51 struct ti_thermal_data *data = container_of(work, 52 struct ti_thermal_data, thermal_wq); 53 54 thermal_zone_device_update(data->ti_thermal); 55 56 dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n", 57 data->ti_thermal->type); 58 } 59 60 /** 61 * ti_thermal_hotspot_temperature - returns sensor extrapolated temperature 62 * @t: omap sensor temperature 63 * @s: omap sensor slope value 64 * @c: omap sensor const value 65 */ 66 static inline int ti_thermal_hotspot_temperature(int t, int s, int c) 67 { 68 int delta = t * s / 1000 + c; 69 70 if (delta < 0) 71 delta = 0; 72 73 return t + delta; 74 } 75 76 /* thermal zone ops */ 77 /* Get temperature callback function for thermal zone*/ 78 static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal, 79 unsigned long *temp) 80 { 81 struct thermal_zone_device *pcb_tz = NULL; 82 struct ti_thermal_data *data = thermal->devdata; 83 struct ti_bandgap *bgp; 84 const struct ti_temp_sensor *s; 85 int ret, tmp, slope, constant; 86 unsigned long pcb_temp; 87 88 if (!data) 89 return 0; 90 91 bgp = data->bgp; 92 s = &bgp->conf->sensors[data->sensor_id]; 93 94 ret = ti_bandgap_read_temperature(bgp, data->sensor_id, &tmp); 95 if (ret) 96 return ret; 97 98 /* Default constants */ 99 slope = s->slope; 100 constant = s->constant; 101 102 pcb_tz = data->pcb_tz; 103 /* In case pcb zone is available, use the extrapolation rule with it */ 104 if (!IS_ERR(pcb_tz)) { 105 ret = thermal_zone_get_temp(pcb_tz, &pcb_temp); 106 if (!ret) { 107 tmp -= pcb_temp; /* got a valid PCB temp */ 108 slope = s->slope_pcb; 109 constant = s->constant_pcb; 110 } else { 111 dev_err(bgp->dev, 112 "Failed to read PCB state. Using defaults\n"); 113 } 114 } 115 *temp = ti_thermal_hotspot_temperature(tmp, slope, constant); 116 117 return ret; 118 } 119 120 /* Bind callback functions for thermal zone */ 121 static int ti_thermal_bind(struct thermal_zone_device *thermal, 122 struct thermal_cooling_device *cdev) 123 { 124 struct ti_thermal_data *data = thermal->devdata; 125 int id; 126 127 if (!data || IS_ERR(data)) 128 return -ENODEV; 129 130 /* check if this is the cooling device we registered */ 131 if (data->cool_dev != cdev) 132 return 0; 133 134 id = data->sensor_id; 135 136 /* Simple thing, two trips, one passive another critical */ 137 return thermal_zone_bind_cooling_device(thermal, 0, cdev, 138 /* bind with min and max states defined by cpu_cooling */ 139 THERMAL_NO_LIMIT, 140 THERMAL_NO_LIMIT); 141 } 142 143 /* Unbind callback functions for thermal zone */ 144 static int ti_thermal_unbind(struct thermal_zone_device *thermal, 145 struct thermal_cooling_device *cdev) 146 { 147 struct ti_thermal_data *data = thermal->devdata; 148 149 if (!data || IS_ERR(data)) 150 return -ENODEV; 151 152 /* check if this is the cooling device we registered */ 153 if (data->cool_dev != cdev) 154 return 0; 155 156 /* Simple thing, two trips, one passive another critical */ 157 return thermal_zone_unbind_cooling_device(thermal, 0, cdev); 158 } 159 160 /* Get mode callback functions for thermal zone */ 161 static int ti_thermal_get_mode(struct thermal_zone_device *thermal, 162 enum thermal_device_mode *mode) 163 { 164 struct ti_thermal_data *data = thermal->devdata; 165 166 if (data) 167 *mode = data->mode; 168 169 return 0; 170 } 171 172 /* Set mode callback functions for thermal zone */ 173 static int ti_thermal_set_mode(struct thermal_zone_device *thermal, 174 enum thermal_device_mode mode) 175 { 176 struct ti_thermal_data *data = thermal->devdata; 177 178 if (!data->ti_thermal) { 179 dev_notice(&thermal->device, "thermal zone not registered\n"); 180 return 0; 181 } 182 183 mutex_lock(&data->ti_thermal->lock); 184 185 if (mode == THERMAL_DEVICE_ENABLED) 186 data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE; 187 else 188 data->ti_thermal->polling_delay = 0; 189 190 mutex_unlock(&data->ti_thermal->lock); 191 192 data->mode = mode; 193 thermal_zone_device_update(data->ti_thermal); 194 dev_dbg(&thermal->device, "thermal polling set for duration=%d msec\n", 195 data->ti_thermal->polling_delay); 196 197 return 0; 198 } 199 200 /* Get trip type callback functions for thermal zone */ 201 static int ti_thermal_get_trip_type(struct thermal_zone_device *thermal, 202 int trip, enum thermal_trip_type *type) 203 { 204 if (!ti_thermal_is_valid_trip(trip)) 205 return -EINVAL; 206 207 if (trip + 1 == OMAP_TRIP_NUMBER) 208 *type = THERMAL_TRIP_CRITICAL; 209 else 210 *type = THERMAL_TRIP_PASSIVE; 211 212 return 0; 213 } 214 215 /* Get trip temperature callback functions for thermal zone */ 216 static int ti_thermal_get_trip_temp(struct thermal_zone_device *thermal, 217 int trip, unsigned long *temp) 218 { 219 if (!ti_thermal_is_valid_trip(trip)) 220 return -EINVAL; 221 222 *temp = ti_thermal_get_trip_value(trip); 223 224 return 0; 225 } 226 227 /* Get the temperature trend callback functions for thermal zone */ 228 static int ti_thermal_get_trend(struct thermal_zone_device *thermal, 229 int trip, enum thermal_trend *trend) 230 { 231 struct ti_thermal_data *data = thermal->devdata; 232 struct ti_bandgap *bgp; 233 int id, tr, ret = 0; 234 235 bgp = data->bgp; 236 id = data->sensor_id; 237 238 ret = ti_bandgap_get_trend(bgp, id, &tr); 239 if (ret) 240 return ret; 241 242 if (tr > 0) 243 *trend = THERMAL_TREND_RAISING; 244 else if (tr < 0) 245 *trend = THERMAL_TREND_DROPPING; 246 else 247 *trend = THERMAL_TREND_STABLE; 248 249 return 0; 250 } 251 252 /* Get critical temperature callback functions for thermal zone */ 253 static int ti_thermal_get_crit_temp(struct thermal_zone_device *thermal, 254 unsigned long *temp) 255 { 256 /* shutdown zone */ 257 return ti_thermal_get_trip_temp(thermal, OMAP_TRIP_NUMBER - 1, temp); 258 } 259 260 static struct thermal_zone_device_ops ti_thermal_ops = { 261 .get_temp = ti_thermal_get_temp, 262 .get_trend = ti_thermal_get_trend, 263 .bind = ti_thermal_bind, 264 .unbind = ti_thermal_unbind, 265 .get_mode = ti_thermal_get_mode, 266 .set_mode = ti_thermal_set_mode, 267 .get_trip_type = ti_thermal_get_trip_type, 268 .get_trip_temp = ti_thermal_get_trip_temp, 269 .get_crit_temp = ti_thermal_get_crit_temp, 270 }; 271 272 static struct ti_thermal_data 273 *ti_thermal_build_data(struct ti_bandgap *bgp, int id) 274 { 275 struct ti_thermal_data *data; 276 277 data = devm_kzalloc(bgp->dev, sizeof(*data), GFP_KERNEL); 278 if (!data) { 279 dev_err(bgp->dev, "kzalloc fail\n"); 280 return NULL; 281 } 282 data->sensor_id = id; 283 data->bgp = bgp; 284 data->mode = THERMAL_DEVICE_ENABLED; 285 /* pcb_tz will be either valid or PTR_ERR() */ 286 data->pcb_tz = thermal_zone_get_zone_by_name("pcb"); 287 INIT_WORK(&data->thermal_wq, ti_thermal_work); 288 289 return data; 290 } 291 292 int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id, 293 char *domain) 294 { 295 struct ti_thermal_data *data; 296 297 data = ti_bandgap_get_sensor_data(bgp, id); 298 299 if (!data || IS_ERR(data)) 300 data = ti_thermal_build_data(bgp, id); 301 302 if (!data) 303 return -EINVAL; 304 305 /* Create thermal zone */ 306 data->ti_thermal = thermal_zone_device_register(domain, 307 OMAP_TRIP_NUMBER, 0, data, &ti_thermal_ops, 308 NULL, FAST_TEMP_MONITORING_RATE, 309 FAST_TEMP_MONITORING_RATE); 310 if (IS_ERR(data->ti_thermal)) { 311 dev_err(bgp->dev, "thermal zone device is NULL\n"); 312 return PTR_ERR(data->ti_thermal); 313 } 314 data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE; 315 ti_bandgap_set_sensor_data(bgp, id, data); 316 317 return 0; 318 } 319 320 int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id) 321 { 322 struct ti_thermal_data *data; 323 324 data = ti_bandgap_get_sensor_data(bgp, id); 325 326 thermal_zone_device_unregister(data->ti_thermal); 327 328 return 0; 329 } 330 331 int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id) 332 { 333 struct ti_thermal_data *data; 334 335 data = ti_bandgap_get_sensor_data(bgp, id); 336 337 schedule_work(&data->thermal_wq); 338 339 return 0; 340 } 341 342 int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id) 343 { 344 struct ti_thermal_data *data; 345 346 data = ti_bandgap_get_sensor_data(bgp, id); 347 if (!data || IS_ERR(data)) 348 data = ti_thermal_build_data(bgp, id); 349 350 if (!data) 351 return -EINVAL; 352 353 if (!cpufreq_get_current_driver()) { 354 dev_dbg(bgp->dev, "no cpufreq driver yet\n"); 355 return -EPROBE_DEFER; 356 } 357 358 /* Register cooling device */ 359 data->cool_dev = cpufreq_cooling_register(cpu_present_mask); 360 if (IS_ERR(data->cool_dev)) { 361 dev_err(bgp->dev, 362 "Failed to register cpufreq cooling device\n"); 363 return PTR_ERR(data->cool_dev); 364 } 365 ti_bandgap_set_sensor_data(bgp, id, data); 366 367 return 0; 368 } 369 370 int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id) 371 { 372 struct ti_thermal_data *data; 373 374 data = ti_bandgap_get_sensor_data(bgp, id); 375 cpufreq_cooling_unregister(data->cool_dev); 376 377 return 0; 378 } 379